bi amping: martin logans

Autor

Beitrag

enety
Neuling

#1 erstellt: 26. Nov 2003, 00:01

hello everyone,
here's my thing:
I have a pair of Martin Logan Sequel 2's.
I am interested in bi-amping them, but i was wandering if anyone can give me some real-world advice. I plan to use this configuration:

bass amp: Rotel 2X60W power amp.
electrostatic membrane: Meridian 2X55W (model 551).

I was wandering if anyone knows if these are powerful enough for my speakers. I did read the manual which states one should use a "50 to 200W" amp - this has no mention of biamping.

actually, I HAVE tried biamping my speakers, with two 2X150W amps, but they would overheat (go into protection).

I have later discovered that my membranes were worn out.
I understand the impedance of a worn out membrane decreases.
I believe that was the reason for the overheating of the amps.
I have recently repaired my speakers, replaceing the worn out membranes with brand new ones.
I am wondering if anyone has a clue whether the new amps will overheat as well ?
they are within the speaker's recommended power rating, and the membranes are brand new. so, does anyone have some experiance ? a hint ?
thank you very much,
Eitan

Manek
Inventar

#2 erstellt: 26. Nov 2003, 12:35

amplifier over heating results from low sensitivity and low impedence of the speaker where they have to work ultra hard to keep up with the droping impedence..

worn out membranes ? how old were they ?

Secondly use an amp with high current capability...with torroidal transformers....and a continuous power rating of 50W above. An amp which will run well even on 4 ohms of continuous load dishing out a minimum of 50W per channel. Rotel would be a solid choice, NAD are pretty good with these situations as they have automatic impedance sensing circuitry which gives out high current or high voltage as the situation and speaker load demands, on the fly. This technolgy is patented by them so you wont find it in any other amplifier but NAD. This way the NAD keeps its cool.

But I suggest you ask a martin logan dealer or the company themselves on tips on bi-amping these particular pair of speakers...I've heard that logans can be pretty difficut to drive....

I have experience with Cadence electrostatic speakers which are made to be valve friendly and I have not faced any issues with the cadence as their sensitivity is rather like a normal speaker, 88db at 8 ohms and I know of cadence users whose membranes have lasted over 9 years and are still going strong...

sledgehammer
Stammgast

#3 erstellt: 27. Nov 2003, 08:58

how old are they when the membranes are already worn out? and yes you should ask martin logan on good amps which have enough power to let your speakers sound as good as possible.

Manek
Inventar

#4 erstellt: 27. Nov 2003, 14:11

also please make sure you have connectors at the ends of the speaker wire on both sides....corroded/oxidised open wire ends with bad contacts also could add to aplifier trouble since logans are hard to drive anyways.